1. Technical Field
The disclosure relates to Sight source structures of projectors, and particularly to a light source structure having solid state light elements and parallel beams for transmission.
2. Description of Related Art
Critical requirements for light sources for projectors are high brightness level and high luminance. Light sources for projectors include non-solid state lighting sources or solid state lighting sources. Current non-solid state lighting sources include tungsten-halogen lamps, metal-halogen lamps, high-pressure mercury-vapor lamps, and xenon lamps. Non-solid state lighting sources have high brightness level, and include elliptical reflectors or parabolic reflectors to reflect the radial beams into parallel beams for further projection. However, these non-solid state lighting sources have defects of excessive heat generation, bulkiness, and high energy consumption. Further, they contain toxic substances, such as mercury that is unrecyclable.
Many projectors use solid state light devices, including light-emitting diodes, or laser diodes, to replace conventional non-solid state lighting sources. Solid state lighting sources have high color saturation; however, they lack such elliptical reflectors or parabolic reflectors to enhance luminance. Therefore, it is desirable to have light source structures of high brightness, high luminance, and use non-toxic materials for projectors.